What to check
If the Request To Exit (RTE) button fails in open circuit mode, then short RTE1 & 0V to test unit.
If the RTE button fails in short circuit mode the door will be kept open
Corrective Action
Replace RTE button.
Additional notes
PB-VR
PB-/EXT/W
Links
https://www.entryphone.co.uk/shop/productdetail/PB-VR
https://www.entryphone.co.uk/shop/productdetail/PB-P_EXT_S